USGS Volcano Notice - DOI-USGS-HVO-2022-12-20T10:35:08-08:00

Activity Summary: Kīlauea Volcano is not erupting. All recent eruptive activity in the Halemaʻumaʻu crater has ceased. No other significant changes have been observed at the summit or in either rift zone.

Summit Observations: Volcanic tremor is weak to nonexistent. Tilt records show deflation-inflation events (DI-events) over the past week and have been stable within long term inflationary trends. GPS data continue along inflationary trends. A sulfur dioxide (SO2) emission rate of approximately 200 tonnes per day (t/d) were measured on December 14, 2022.

Halemaʻumaʻu Lava Lake Observations: Lava is no longer erupting from the western vent into the lava lake on Halemaʻumaʻu crater floor. The lava lake surface has cooled to form a dark crust. This week saw a few passive events of crustal overturn on December 14-15, which brought fresh incandescent lava to the lake surface from the hot lava lake below. A smaller overturn event occurred on December 17 and another small event started around midnight and continues this morning on Dec 20. Measured last on October 28, 2022, the total cumulative rise of the crater floor has been about 143 meters (469 feet), and 111 million cubic meters (29.2 billion gallons) of lava had been effused since the beginning of the latest eruption on September 29, 2021.

East Rift Zone Observations: No unusual activity has been noted along the East Rift Zone or Southwest Rift Zone; steady rates of ground deformation and seismicity continue along both. Measurements from continuous gas monitoring stations downwind of Puʻuʻōʻō in the middle East Rift Zone remain below detection limits for SO2, indicating that SO2 emissions from Puʻuʻōʻō are negligible.

Hazard Analysis: The latest eruptive activity at Kīlauea's summit occurred within a closed area of Hawaiʻi Volcanoes National Park. High levels of volcanic gas was the primary hazard of concern, as this hazard can have far-reaching effects downwind. Large amounts of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are continuously released during eruptions of Kīlauea Volcano. Even during periods of no eruptive activity passive volcanic degassing from the summit and the lava lake still release volcanic gases. As SO2 is released from the summit, it reacts in the atmosphere to create the visible haze known as vog (volcanic smog) that has been observed downwind of Kīlauea. Vog creates the potential for airborne health hazards to residents and visitors, damages agricultural crops and other plants, and affects livestock. For more information on gas hazards at the summit of Kīlauea, please see: https://pubs.er.usgs.gov/publication/fs20173017. Vog information can be found at https://vog.ivhhn.org.  

Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of the rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since early 2008.   

Additional hazards include Pele's hair and other lightweight volcanic glass fragments from lava fountains that will fall downwind and dust the ground within a few hundred meters (yards) of the erupting fissure vent(s). Strong winds may waft lighter particles to greater distances. Residents should minimize exposure to these volcanic particles, which can cause skin and eye irritation.  
 
For discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards. 
 
Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm. Visitors to Hawaiʻi Volcanoes National Park should note that under southerly (non-trade) wind conditions, there is potential for a dusting of powdery to gritty ash composed of volcanic glass and rock fragments. These ashfalls represent a minor hazard, but visitors should be aware that such dustings at areas around the Kīlauea summit are possible.  
 
The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea Volcano. 
 
HVO will continue to issue weekly Kīlauea Volcano updates until further notice. Additional messages will be issued as needed.